Draft gear



Sept. s, 1925.

w. H. COTTON DRAFT GEAR Filed March 8. 1924 2 Sheets-Sheet l Sept. 8,1925.

w. H. COTTON DRAFT GEAR Filed March 8, 1924 2 Sheets-Sheet 2 i PatentedSept. 8, 1925.

UNITED 'STATES PATENT OFFICE.

WALTER n. COTTON, or c n-IoAoo, ILLINOIS, AssIeNon To IINLON DRAFT enenco., A CORPORATION or ILLINOIS,

DRAFT enna.k

-Applcaton filed. March 8, 1924'. Serial No, 697,925.

To all whom t may concern.'

Be it known that I, VVALTER H. COTTON, 'a citizen of the United States,and resident of Chicago, county of Cook, and State of illinois, haveinventedcertain new and useful Improvements in Draft Gears, of which thefollowing is a. specification and which are illustrated in theaccompanying drawings, forming a part thereof.

The invention relates to draft gears of the friction type for railwaycars, being especially adapted for freight service, its principal objectbeing to secureal high capacity for absorbing and dissipating energy.

A preferred embodiment of the invention is disclosed in the accompanyingdrawings, in which Fig. 1 is a central plan section of the gear inrelease position with parts of the car structure shown in plan, andpartly broken away;

Fig. 2 is a detail side elevation partly in section viewed from the line2-2 of Fig. 1;

Fig. 3 is aview similar to Fig. 1, the gear being under compression inbluff;

Fig. 4E is a detail section on the broken line 4 4 of Fig. 3;

Fig. 5 is a plan view of the gear detached from the car, and

Figs. 6 and 7 are details in perspective of wedging and frictionelements.

For the purpose of showing the manner of mounting the gear on a car,there is shown a pair of draft sills at 10 with draft lugs 11, 11, andbufmg lugs 12, 12, attached thereto. The butt of a coupler is shown at13 and its extension, here shown as a. loop-form of yoke, at 14.

The gear comprises a pair of followers 15, 16, which are enclosed withinthe loop 14 and cooperate respectively with the draft and buliing lugs.Each of these followers is provided with a central wedging extension 17,18, preferably though not necessarily, formed integrally with thefollower. Each follower is also provided with top and bottom plateextensions which interfit as Inortise and tenon joints. As shown at 19,20, Fig. 5, preferably the spaced elements 19 are formed at the top ofone of the followers and at the bottom of the other, and the central orentering elements 20 are 'consequently reversely arranged. n

Cooperating with each of the wedges 17, 18, is a pair of floating wedgevelements 21, 22, 23, 24. The'elements 21, 2 3, are each provided withay bifurcated lateral extension 25, 26, which'frictionally engage eachother on the transverse medial line' of the gear'. The elements 22, 211,are mere blocks, each of which seats against one of the lateralextensions 25, 26. Each of the wedge elements 21, 23, is furtherprovided with a lug 27 (F ig. 2) each of which extends into a recess 28formed in the elements 22, 24, for the pur pose of interlockingtherewithand positively insu-ring Vthe movement together of the two wedgingelements located upon the same side of the gear.

The relative approach of the followers 15, 16, causes the spreading ofthe floating wedge elements as indicated in Fig. 3, land this movementis resisted by a pair of springs 29, 30, mounted upon the end portionsof a transversely disposed stt-raining rod 31, these springs reactingbetween seats, as 32, threaded upon the lrod and seats, as 33, sleevedupon the rod and bearing against the floating wedge elements. Thetransverse faces of the oat-ing wedge elements are grooved to provideclearance for the rod 31, andthe extensions 25, 26, are bifurcated forthe same reason.

Friction is developed not only between the several faces, but especiallybetween the eX- tensions or plates 25, 26, which slide'upon each otheras the gear is compressed and released. As both of the plates 25, 26,have movement their relative travel is double that of the movable springseats, andas the capacity for absorbing and dissipating energy is inproportion both to the pressure upon and extent of movement of theengaging ele ments, the capacity of the gear consequently is very high.

Inasrnuch as these plates move in line with the springs the frictiondeveloped between them supplements the spring resistance and makes itpossible to use lighter springs than have ordinarily been employed ingears of this general type. Y

The wedge elements 21 to 211 ride upon the instanding webs 19, 20, ofthe followers. The gear reaches the limit of its compression when theflattened ends of the wedges 17, 18, come into contact with the plates25, 26, as shown in Fig. 3.

Although the form of construction'shown and described is, so far as nowadvised, mostolesirable, the scope of the invention is such as toinclude various modifications of it. For example, while the frictionplates 25, 25, are shown as being cast or formed integrally with one ofthe wedge elements, they will function the same if merely interlockedtherewith.

I claim as my invention:

l. In a draft gear, in combination, a pair of springs disposed normal tothe axis of the gear, a pair of coacting relatively movable frictionplates parallel with the springs and lsupplementing their resistance andmeans for simultaneously moving the plates in o-pposite directions andcompressing the springs.

2. In a draft gear, in combination, a pair of followers, a spreadingwedge associated with each follower, a pair of wedge elementscooperating with each of the spreading wedges, a pair of cooperatingfriction plates one thereof being associated and movable with one of thewedge elements of each pair, and spring means resisting the movements ofthe named parts.

3. In a draft gear, in combination, a pair of coacting friction platesdisposed transversely to the axis of the gear, a wedging elementassociated and movable with each plate, a wedging element opposed toeach of the last named wedging elements and sli'dably seated upon theplate associated therewith, a pair of followers each having a spreadingwedge entered between the pair of wedging elements at the adjacent sideof the plates, and spring means resisting the movement of such parts.

4t. In a draft gear, in combination, a` pair of coacting friction platesdisposed transversely to the aXis of the gear, a wedging elementassociated and movable with each plate, a wedging element opposed toeach of the last named wedging elements and slidably seated upon theplate associated therewith and being inter-locked wit-h the wedgeelement associated with the other plate, a pair of followers each havinga spreading wedge entered between the pair of wedging elements at theadjacent side of the plates, and spring means resisting the movement ofsuch parts.

In a draft gear, in combination,'two pairs of opposed wedging elements,a pair of coacting friction plates interposed between the two pairs,each plate being fixed to one of the elements and slidingly engaging theother element of the same pair, a pair of followers each having aspreading wedge entered between the wedging eled ments of one of thepairs and spring means opposing the spreading action thereon.

6. In a draft gear, in combination, a tension rod disposed transverselyto the airis of the gear and provided with a pair of sleeves, springmeans urging the sleeves toward each other, two pairs of opposed wedgingelements interposed between the sleeves, a pair of coacting frictionplates interposed between the two pairs of wedging elements, one ofsuch, plates being in fixed relation with one of such elements and insliding engagement with the other element of the same pair, and a pairof followers each having a spreading wedge entered between the membersof the adjacent pair of opposed wedging elements.

WALTER H. COTTON.

